Condenser finning machine



Dec. 10, 1940. w, O'BRIEN 2,224,549

CONDENSER FINNING MACHINE Filed Oct. 26, 1936 9 Shets-Sheet 1 llllllllHllllH 'Dec. 10, 1940.

W. L. O'BRIEN CONDENSER FINNING MACHINE Filed Oct. 26, 1936 9 Sheets-Sheet 2 W Wm W5 Dec. 10, 1940. w L O'BRIEN 2,224,549

CONDENSER FINNING MACHINE Filed Oct. 26, 1936 9 Sheets-Sheet 3 INVENTOR FVL ZZ [11m L. O'Brien ATTORN EYS Dec; 10, 1940.

Filed Oct. 26, 1936 9 Sheets-Sheet 4 n M e w 7 S w 5 .m L Mo 1,. n n A .m Z $3 W 6 LEI Dec. 10, 1940. w o' A 2,224,549

CONDENSER FINNING MACHINE Filed Oct. 26, 1936 9 Sheets$heet 5 226 v INVENTOR Z4 m'lliam L. 0 5712% 288- 38 BY 284 2 4 ATTORNEYS Dec. 10, 1940. w. L. O'BRIEN CONDENSER FINNING MACHINE Filed Oct. 26, 1936 9 Sheets-Sheet 7 INVENTOR fl zlliam L. QBrien 434m, QM

ATTORNEYS Dec. 10, 1940. w. OBRIEN CONDENSER FINNING MACHINE 9 Sheets-Sheet 8 Filed Oct. 26, 1956 INVENTOR William L. QBrien BY w 41mm; 19M

ATTORNEYS Dec. 10, 1940. w. L. O'BRIEN CONDENSER FINNING MACHINE 9 Shets-Sheet 9 Filed Oct. 26, 1936 ATTORN EYS INVENTOR William L.0Erien Patented Dec. 10, 1940 UNITED STATES CONDENSER FINNING MACHINE William L. O'Brien, Evansville, Servel, Inc., New Yor-KN. Y

Delaware Ind.,ass tnor to a-co 'l oration of Application October 26, 1936, Sei'lal No. 107,739

19 Claims.

This invention relates to sheet metal working machines, and more in particular to machines for making condenser fins from sheet metal and for placing the fins upon condenser pipes.

An object of this invention is to provide an automatic machine which will make sheet metal members and place them in spaced relationship upon longitudinal members, such as pipes.

In the illustrative embodiment shown:

Figure 1 is a side view of the machine with the fin-material-holding means (shown at the right) moved up to the press and with a portion of the adjacent brake control rod 95 cut away;

Figure 2 is a vertical section of the machine;

Figure 2a is a view of the main power shaft from the line Za-Za of Figure 2;

Figure 3 is a view oi the machine from the side opposite to that shown in Figure 1;

Figures 3a, 3b and 3c are detail views of latch means later to be described;

Figure 4 is a view of the means for assisting in holding a set of U-tubes in position;

Figure 5 is a view showing the U-tube-holdin 25 means and the fin-cutting means;

Figure 6 is an end view of the elements shown in Figure 5 with various portions cut away so as to show the detailed structure;

Figure 7 is an enlarged view of the fin cutter;

Figure 7a is a sectional view on the line la-1a of Figure 8;

Figure 8 is a horizontal section of a portion of the machine in the path of the fin-material feeding therethrough and showing (at the lower 35 part of the figure) one of the followers in position to receive a fin,'together with the structure for controlling the position of the followers;

Figure 9 is an enlarged view similar to the left-hand central portion of Figure 2, showing 40 the fin-cutting means and the follower control mechanism with portions cut away so as to show the details;

Figure 10 is a view similar to Figure 9, showing 45 the follower control mechanism in a different position;

Figure 11 is a sectional view similar to a portion of Figure 2 but showing the parts in a different position;

Figure 12 is a vertical section of the follower moving mechanism Figure 13 is an enlarged sectional view of a portion of Figure 12 showing certain details;

Figure 14 is an enlargement of the right-hand as central portion of Figure 2;

Figure 15 is a vertical section showing the details of the safety stop mechanism;

Figure 16 is a side elevation of the safety stop me"hanism;

Figure 17 is-a view of the stop shaft showing the elements which are rigidly mounted thereon;

Figure 18 is a view from the right side of Figure 1 showing the stitcher for connecting the strips of fin material to each other to insure continuous feed, and the oiler mechanism;

Figure 19 is a top view thereof;

Figure 20 is an elevation of the stitcher, showing the element (which cuts the ends of the strips of fin material preparatory to stitching) in the down position, and with portions of the various .elements cutaway so as to show details of the structure;

Figure 21 is a sectional view on the line i i-2i of Figure 20;

Figure 22 is a view similar to showing the cutter element in tion; and

Figure 23 is an enlarged view of certain parts shown in Figure 21, showing the cutter (at the left) in its upper position and the adjacent stitcher in its down position.

In heat exchange elements, such as condensers, radiators and evaporators, where it is desirable either to add heat or take heat away from fluid within tubes or pipes, metallic fins may be provided upon the tubes to carry heat from or to the tubes, as the case may be. In the manufacture of these heat exchange elements, the tubes may be made up of U-shaped portions upon which the fins may be placed. If desirable, a set may include two or more U-tubes placed parallel to each other and the fins may be placed upon all of them at the same time. After the fins are in place, the U-tubes may be joined together so as to form a continuous circuit.

The preferred embodiment of the present invention is a machine for making the fins for a condenser from a strip of sheet metal and for placing the fins upon U-tubes in spaced relationship.

Referring to the right-hand portion oi. Figure 1 of the drawings, a strip of sheet metal, which is the fin material and is designated by the numeral B, is shown in the form of a coil held by a holder ill. The end of strip 8 is unwound 50 and extends to the left through press I00 which has (as best shown in Figure 3) a main power shaft i34 driven by motor I40 through belt I38 running upon fly-wheel pulley I36, there being a fiy-wheel clutch of any usual type (not shown) 55 Figure 21 but its upper posiconnecting fly-wheel pulley III with shaft I34. Referring to Figure 2, during operation of the l machine, strip I is advanced to the left through press' III where rows of flanged holes are formed across strip I at spaced points. To the left of press I00, in the path of strip I, is cutter III which, as best shown in Figure 9, cuts from strip I individual fins. 7 Referring to the upper portions of Figures 5 and 6, particularly the latter, directly below the flanged holes I08 in the strip end I, when strip end 8 is in position to be cut from strip I to form a fin, are the ends of a set of three U- 7 tubes I4I which are held in place by the large I0 sliding rack I42. Fitted upon each end of each of the U-tubes I is a round-nosed plug I44 which is held in place by an extension I48 which extends into the end of the tube. Plugs I44 have a maximum diameter the same as the outside diameter of the tubes, and are adapted to enter the flanged holes in fin 8 and effectively position the ends of the U-tubes therein.

Referring to the left-hand portion of Figure '2, a plurality of angular-1y shaped followers 202 are carried upon two endless chains (only one of which is shown) and are the active elements of the fin-positioning means. As each fin 8 is cut from strip 8, it is pushed by a follower 202 downwardly along U-tubes I4I and properly spaced thereon.

Referring particularly to Figure 2a and the upper right-hand portion of Figure 2, the main shaft I34 has rigidly mounted thereon two ec centrics I0I upon each of which is mounted a pitman I05 which extends downwardly and upon the end of which is mounted plunger head IOI. Plunger head IN is adapted to move up and down, and in such movement is guided by means (not shown) upon the inside of each side memher of the press. Upon the bottom face of plunger head IN is fixed the block I02 of the perforating mechanism which is shown enlarged in Figure 14.

Directly below the block. I02 is the anvil I03 5 of the perforating mechanism. Elements I02 and I03 cooperate in such a way that rows of holes are punched in the strip of fin material traveling therebetween, and then the metal around each hole is expanded into a flange. Each row of holes extends across the width of the strip and is so positioned that it is alon the center line of the metal that will later be a fin. There are six holes in each row, and

the means for producing one of the holes is shown in cross-section. This is a cutting pin I04 fixed in block I02 and a cooperating hole I08 in anvil I03. Surrounding hole I08 is an upstanding sleeve I08, andsurrounding pin I04 is a sliding sleeve II2 which may move up and down relative to pin I04 in the circular opening IIO formed in block I02. The lower end of sleeve II2 slides freely in collar II3 which is rigidly mounted in block I02, there being an enlargement upon the upper end of sleeve II2 which acts as a stop means. Surrounding the upper end of pin I04 and exerting pressure upon the upper end of sleeve II2, so as normally to hold sleeve II2 in its lowermost position, is spring III. After cutting pin IM'enters hole I08 and as block I02 moves farther downwardly, sleeve I08 enters recess H5 in collar H3 and, in doing so, forms an upwardly extending, sharpedged flange I09 (see Figure 6) around the hole, the flange entering recess H5. Recess H5 is slightly larger in diameter than sleeve I08 so asce ic downwardly, sleeve II2 is engaged and held stationaiy by the upper end of sleeve III. As will be explained later, this flanged hole is formed to fit upon a condenser pipe.

When block I02 has reached its lowest position and starts upwardly again, sleeve II2 is pushed downwardly with respect to block I02 by spring III, so as to free the flange I09 from recess II5.

As best shown in Figure 2, the material cut from strip 8 in forming holes falls to the bottom of the press through suitable openings to a container Ill. The forming of flange I08 is facilitated by oil which is placed upon the bottom surface of strip 8 as it enters the press by the oiler 4".

Referring again to Figure 14, to the left of the hole-and-fiange-forming mechanism and mounted upon block I02 are a pair of material-centering pins II4 which, upon each downward movement of block I02, enter two of the previously formed flanged holes, pass through the holes, and enter openings H8 in anvil I03, with the result that strip 8 is definitely centered during each downward punching operation.

Referring to Figure 2, rigidly mounted to the left'of anvil I03 upon shaft H8 is shown one of a pair of arms H8, upon the free end of each of which is pivotallymounted a feed finger I20. The right end of each of feed fingers is urged downwardly by tension spring I22, the other end of the spring being attached to the frame of the press. The left ends of feed fingers I20 are adapted to enter holes in each row of holes in strip 8. The left end surface of each finger I20 is vertical, while the upper surface of the end of the finger is sloped to form a cam, so that when feed fingers I20 are moved toward the right they will be depressed and retreat from the holes; but when they move toward the left they will enter and remain in the holes and advance strip 8 toward the left. As best shown in dotted lines just below the center of Figures 1 and 3, shaft H8 is actuated by arms I2I mounted near the ends thereof which, in turn, are actuated by rods I23. The other ends of rods I23 are carried by arms I 24 whichare fixably mounted upon shaft I26. Referring to,

Figure 1, shaft I28 also has fixably mounted thereon arm I28, the free end of which carries one end of eccentric rod I30. The other end of rod I30 is carried by eccentric collar I32 mounted upon eccentric I33 which is fixed upon the end of power shaft I34.

Upon rotation of shaft I34, eccentric collar I32 and rod I30 cooperate so as to translate the rotation into an oscillating motion at the lower end of rod I30. This oscillating motion is transmitted through arm I28, shaft I26, arms I24, rods I23 and arms I2I to shaft 8; with the result that (see Figure 2) arms H9, and with them feed fingers I20, oscillate ratchet-wise through a definite path of definilte length so as to feed strip 8 in measured steps.

Eccentric I33 is mounted upon power shaft I34 so that this path is such as to cause feed fingers I 20 to advance strip 8 a distance equal to the width of one fin, and so as to move feed fingers I20 to the left and thus advance strip 8 while block I02 is raised and is thus free from strip 8. In this way, feed fingers I20 advance the fin material the width of one fin immediately after a row of flanged holes has been formed, and then are returning so as to enter holes in the next assume row during the time that block I82 is engaging strip 8 to form another row of flanged holes. Thus, the holes in strip 8 are spaced in a definite relationship with respect to the cutter and the hole-forming mechanism. The extreme position of fingers I20 to the left may be controlled and determines the exact position of strip 8 during the hole-forming and the cutting operations. This allows for ready adjustment of the width of the fins and, at the same time, avoids errors justably carried by sliding block I58 which is mounted upon guide pins I58 so as to move ve'rtically. Guide pins I58 are slidably mounted at the top and bottom in bearings, the lower bearings being carried by base block I53, and the upper bearings being carried by block I58 which is mounted.at its ends upon base block I 53.

Referring again to the central portion of Figure 2, extending from the left side of plunger head IN is actuating arm I60, the end of which enters a recess in the right side of block I56. Due to this construction, as plunger head I0l moves carrying block I02 it also carries with it movable cutter I54; and when the movement is downwardly a fin is cut from the end of the strip. Simultaneously, a row of flanged holes is formed in the strip between block I02 and anvil I03. As pointed out above, the spacing between block I02 and cutter I54 is such that as strip 8 is moved the width of one fin in the interval between two downward movements of plunger head IOI, strip 8 is left in a new position such that a portion of strip 8, equal to the width of one fin, extends beyond the cutting edge of cutter I50. A row of flanged holes which were formed during a previous downward movement of block I02 is spaced along a line which is the center lln of the extending portion.

Referring again to Figure '1, the cutting edge of the fixed cutting element I52 is formed of five distinct portions, each of which cooperates with" a corresponding portion of the cutting edge of the movable element I54. The main portion of the cutting edge of the fixed element is straight and is designated by the numeral I62, and terminates at its ends in arcuate portions I63. Edges I62 and I63 are in the horizontal plane of surface I64 which is the plane of the path of strip 8 as it travels through press I00. Spaced slightly below surface I64 and in the horizontal plane of surfaces I61, are arcuate edges I 66 which extend from points which are in vertical alignment with the points of juncture between edge I62 and edges I63.

Fixed cutter element I52 is cut out behind edges I66 and below edges I63 so as to form recesses, of which the bottom surfaces I65 slope downwardly and backwardly. As best shown in Figure 10., these recesses open into passages I 60 in base block I53, which (see Figure 2). communicate with chutes I10 leading into the bottom of the press. This facilitates disposal of waste pieces cut from strip 8.

Referring again to Figure 7, the upper cutting member is provided with a straight center edge I88 which terminates at its ends in arcuate extending edges I12. Edges I88 and I12 allform edges of horizontal surface I14. Spaced above surface I14 the same distance that surface I84 is above surfaces I81 are arcuate edges l15 which form edges of horizontal surfaces I18. Movable cutter element I54 is cut out upwardly from edges I15 and I88 so as to form a recess I18; and thus the upper cutting member fits over and registers with the lower cutting member.

Edges I88, I12 and I15 are in vertical alignment with and are of the same size and shape as edges I82, I88 and I88, respectively.

In explaining the operation of the cutter, consider that a strip of fin material 8 rests upon surface I84 and extends beyond edge I62 a distance equal to the width of one fin (as shown in Figure 8). Referring now to Figure 7, as movable cutter element I54 descends, surface I 14 will engage the top of the fin material and thrust downwardly thereon. Upon further downward movement, cutting edge I68 will cooperate with cutting edge I 82 so as to cut the fin free from strip 8 except at its extreme ends, that is, the sides of strip 8. During this first cutting operation and for a short time thereafter, surface I14 has not reached the plane of surface I81 and cutting edges I12 and I68 have not yet come into cutting cooperation. Similarly, surfaces I18 have not reached the plane of surface I64, and cutting edges I15 and I83 cannot yet cooperate. During this short period of time after the center portion of the fin has been out free and before surfaces I14 and I16 reach surfaces I61 and I64, respectively, the fin is pushed downwardly by surface I14, but is held at its ends (Figure 8) by the narrow and still uncut portions I80.

As cutter element I 54 moves further downwardly, cutting edges I 66 and I63 meet cutting edges'l12 and I15, respectively, so as to cut out a portion I80 at each side of strip 8 and thus cut fin 9 entirely free from strip 8 and, at the same time, round the adjacent corners of fin 8 and the end of strip 8. These portions I80 fall upon surfaces I65 and slide downwardly through passages I69 and (see Figure 2) through chutes I10 to container H1 in the bottom of the press.

Fin-positioning mechanism The mechanism for spacing the fins upon a set of the U-tubes is entirely automatic after it is once started, and receives each fin individually as it'is cut from strip 8 and places it in the proper position upon the U-tubes. This mechanism includes followers which are carried between two endless chains and which, during the operative portion of their movement, move continuously downwardly along one side of the U- tubes.

As best shown in Figure 2, followers 202 are mounted upon shafts 204 and are allowed to rock between the two positions shown, butare normally biased counter-clockwise to the posi-- tion shown in the bottom half of the figure. There are a large number of identical followers and one will be described in detail, together with its mounting means.

The means for biasing follower 202 is shown best in Figure 8 and is a spring 206 mounted upon the center of and attached at one end to shaft 204. The other end of spring 206 is attached to follower 202. The upper portion of follower 202 (see also Figure 10) is provided with a paddle 248; and the lower portion (see Figure 8) has two sleeve journals 244 and 245 which are rotatably mounted upon shaft 284. Paddle 248 is substantially thelength of fin 8 and is provided with fingers 248 which fit tightly about a portion of the periphery oi the flanges I09 and extend between the U-tubesso as to exert force upon the fins in such a way as to avoid distor-; tion of the fins.

Follower 202 also carries, along its center line,

roller 250 which is rotatably mounted (see Figure 10) upon a'shaft 25] above and to the left of shaft 204. Referring now to Figure 8, freely mounted upon shaft 204 adjacent the inner end of sleeve journal 244 is actuating roller 252. A web-supporting structure 24! connects sleeve journals 244 and 245 over the top of roller 250.-

Shaft 204 is fixedly mounted at its two ends in link bracket 208 which are in pairs, each pair forming a link of one of the two endless chains 209. Upon the ends of shaft 204 are extensions upon which are mounted roller bearing elements 2i0 which are held by guide strips 2 so as to ride in vertical grooves H2 and M3. These grooves are in frame members 2 and H5, respectively, and guide the followers as they move downwardly along the side of the U-tubes.

Referring to Figures 2 and 12, frame members 2 and 2i5- also act as mounting means for the other parts of the follower control mechanism and for this purpose, mounted in bearings at the top and bottom of frame members 2 and H5, are shafts 2l8 and 220. Upon shafts 2I6 and 220 are fixedly mounted two pairs of sprocket wheels 218 and 222, respectively, which carry endless chains 209, referred to above.

Supported by suitable web structure upon frame members 2l4 and 2 l5, and located vertically therebetween, is slide support channel 224. As best shown in Figure 8, slide support channel 224 is substantially U-shaped in horizontal crosssection and its interior channel 226 provides a guideway for the reciprocating slide 228.

Reciprocating slide 228 comprises two side members 229 and roller strip face 230' which are welded together and are reenforced (see Figure 9) at the top by cam member 23i and at the bottom by blocks 22'! and 233.

Referring to Figure 12, mounted on the righthand side and near the top of slide 228 upon suitable adjustable mounting means is release pin 293, the purpose of which will be explained later. The mounting means for release pin 293 is shown in Figure 13 and comprises a fixed block 29i riveted to side member 229 upon which is adjustably mounted an adjustable block 292. Upon the outer face of fixed block 29| are horizontal grooves 295 and upon the adjacent face of adiustable block 292 are cooperating teeth 296. Adjustable block 292 is provided with a vertical slot 297 which is adapted to receive set screw 299 which is screwed into fixed block 29l. Adjustment of release pin 293 is obtained by releasing set screw 299, positioning teeth 296 in the proper grooves 295 and then tightening set screw 299. Release pin 293 is hood-shaped and is mounted upon a stud 294 which is screwed into block 292 and which is locked in place by tightening up release pin 293.

Reciprocating slide 228 acts as a control means to control the position of the followers as they move downwardly, rocking the followers in position to engage the fins and then allowing the followers to retract and release the fins at the proper points. Thus, slide 228 actually controls the positions in which the fins are placed on the U-members.

Slide 228 is adapted to move in channel 228 between the lower position, shown in Figure 11, and the upper position, shown in Figure 2; and is held in channel 228 by three pairs of guide rollers 232 which are carried near the top, center and bottom of slide 228. As-best shown in'Figure 8, guide rollers 232 are held in channel 228 by guide plates 236 and, as shown in dotted lines in Figure 12, are carried upon the ends of pins 234.

Referring also to Figure 2, mounted in the back and extending from the bottom to a point slightly above the middle of channel 228 is rack 238. As best shown in Figure 9, pivotally mounted near the bottom and on the left side of slide 228 are two dogs 240 and242 which are biased by springs 24! and 243, respectively, in a clockwise direction so that they tend to engage the teeth in rack 238. These teeth are shaped so as to have upper faces which are in alignment with the ends of the dogs which cooperate therewith; I

and thus, slide 228 is held from downward movement except when dogs 240 and 242 are withdrawn from their normal position. The lower faces of these teeth are inclined to permit the dogs 240 and 242 to slide over them when slide 228 moves upwardly.

As pointed out above, the followers may rock between two positions, and when in the extended position shown at the top of Figures 9 and i0 and in Figure 8, the paddles 248 extend outwardly to engage the fins as the fins are cut off. In the retracted position shown at the bottom of Figures 9 and 10, the paddle is withdrawn and freed from the fins.

As best shown in Figure 2, as the followers are carried by chains 209 around sprocket whee1s2l8 they are in the retracted position and remain in that position until rollers 250 contact cam member 23| at the top of reciprocating slide 228. As each follower 202 reaches cam member 23l, its roller 250, riding upon cam member 23I, rocks follower 202 clockwise to its extended position. Upon further downward movement of follower 202, roller 250 will ride upon roller strip 230 and thus hold the follower 202 in its extended position.

Referring to Figures 9 and 12, pivotally mounted upon the bottom of slide 228 is pointed actuating arm 254, the pointed free end of which extends downwardly and to the right (Figure 9) into the path of rollers 252. Rotatably mounted between the two side walls 229 of reciprocating slide 228, upon a suitable bearing (see also Figure 8) carried by shaft 258, at a point below pivot 258 is bell crank 280 which has a vertical portion and a horizontal portion; the horizontal portion carrying at the end thereof pin 26i upon which is pivoted dog 240. Extending from the right side (Figure 12) of pointed arm 254 through a slot in the side wall 229 of slide 228 and into engagement with a groove in the top of the vertical portion of bell crank 260 is actuating pin 262.

Referring again to Figure 9, bell crank 260 and pointed arm 254 are normally biased, along with dog 240, by spring 24l to the position shown. As each actuating roller 252 is carried downwardly, it engages the free end of pointed arm 254 and rocks this arm clockwise. This movement of arm 254 is transmitted through pin 282 to bell crank 280 so as to cause bell crank 260 to rotate counter-clockwise. This movement of bell crank 260 causes the bell crank to pivot upon shaft 258 so as to thrust downwardly upon dog 240 and raise slide 228. As slide 228 rises,

fin and is retained in the new position by dog 242.

Considering now that the elements are in the osition shown in Figure 9, the followers are held in their extended position as they pass slide 228 and each is tilted back by its spring as its roller 258 clears the lower end of roller strip 288. Follower 282a is shown moving downwardly and is about to engage fin 9a which is about to be cut from strip 8. As surface I14 (see also Figure '7) moves downwardly so as to engage the uppersurface of fin 9a, and cutting edges I68 and 2 start cutting the middle portion of fin 9a free, the

paddle of follower 282a engages the top of fin9a and pushes downwardly thereon. As explained above (referrin to Figures '7 and 8) as the upper cutting member and follower 282a carry the fin downwardly, the fin is held at its ends by means of portions I88 and flanged holes in the fin are uided over the ends of U-tubes Ml (Figure 9) by round-nosed plugs I44. Upon further movement downwardly, cutting ed es I12 and 515 cooperate with cutting edges I66 and I68, respecively, so as to cut the fin entirely free from strip 8; and the upper cutting member moves upwardly again, while the follower carries the fin downwardlyalong the tubes. In Figure 9, fin 9b has reached the. desired position upon U-tubes Hi and roller 258 upon follower 2826 has cleared the lower end of roller strip 238 so as to allow follower 2828 to be tilted backwards and web 241 has momentarily come in contact with block 293. When web 241 moves free of block 233, follower 282?) will move to its retracted position. In Figure 9, follower 2820 has carried fin 90 to its proper position and is moving on downwardly. Above follower 282a, follower 282d is moving downwardlyso as to receive the next fin which is to be cut from strip 8. Actuating roller 252d upon follower 282d is about to en age pointed arm 2% and thereby elevate slide 228 a distance equal to the spacing between one fin and the adjacent fin. Follower 282a will, therefore, place fin, 8a upon U-tubes l4l at a point properly spaced above fin 9b.

In the normal operation of the machine, at the time fins have been placed throughout the length of a set of U-tubes I, slide 228 has been moved upwardly to the position shown in Figure 2 and the top of the slide engages set screw 264 which is adjustably carried in a vertically slidable bracket 286; and bracket 266 is moved upwardly.

Movement of bracket 266 draws link 268 upwardly which rotates lever 212 and shaft 218 to which lever 212 is keyed. As will be explained later, this rotation of shaft 218 stops the entire machine.

With the machine stopped in the position shown in Figure 2, the finished unit, comprising a set of U-tubes with the desired number of fins thereon, may be removed from the machine and a new set of U-tubes may be properly positioned to receive fins. As best shown in the left-hand portion of Figure 9, horizontal shaft 218 is rotatably mounted and has rigidly mounted thereon arm 288, in the free end of which is fixed horizontal pin 282. Pin 282 engages a horizontal slot in the upper end of dog-disengaging bar 284 which is mounted in channel 226 (see also Figure 8) and which (see Figure 9) has two diagonal slots 286 therein through which fixed pins 286 extend, fixed pins 288 being mounted in slide support channel 224. When a new set of tubes is in position, handle 214 is pulled downwardly against the tension of spring 218 (see also Figure 3) so as to rotate shaft 218 and arm 288 counter-clockwise (Figure 9). This movement raises dog-disengaging bar 284 'which, due to slots 286 riding upon fixed pins 288, when raised, moves to the right from the position shown in Figure 9 to the position shown in Figure 18. When moving to the right, the right edge of dogdisengaging bar 284 contacts the left side of the movable ends of dogs 248 and 242 and moves the dogs out of engagement with rack 238. Dogs 248 and 242 are, therefore, rendered ineffective, and slide 228 moves freely downwardly until block 283 engages the next follower below which is in its retracted position.

This movement of slide 228 is very slight but it is sufficient to move the top thereof (Figure 2) free from set screw 264 and the machine may now be started again. Referring to Figure 9, rockably mounted to the right'of lever 288 upon slide supportchannel 224 is bell crank 288 which has a horizontal portion extending to the right (Figure 9)' along the side of slide 228 into the path of-release pin 293 (see Figure 12) which is fixed to slide 228. Bell crank 289 also has a latch portion extending. upwardly and to the left (Figure 9). Fixedly mounted upon shaft 218 and extending into engagement with the end of the latch portion of bell crank 289 is latch dog 298. Bell crank 289 is biased by spring 298 so that its left end normally tends to move downwardly and so that when shaft 218 is rotated to release dogs 248 and 242 this latch portion falls behind latch dog 298, as shown in Figure 10. This engagement of the latch portion of hell crank 289 with latch dog 298 latches shaft 218, and with it dog-disengaging bar 284 and dogs 248 and 282, in the position shown in Figure 18 so that, even though the operator removes his hand from handle 214, dogs 248 and 242 are still held out of engagement with rack 238.

With the new set of tubes in position, and slide 228 resting upon follower 282', as shown in Figure 10, the machine may be set in operation and the chains will start lowering follower 282' and with it slide 228. During this movement downwardly, slide 228 holds a given number of the followers in the extended position, and as each follower passes the cutter it picks up a fin in the usual manner and carries it downwardly along the tubes, all as previously described. .Reierring to roller 252 engages pointed arm 254 so as to step" slide 228 up a distance equal to the desired spacing between one fin and the adjacent fin, and the next fin is then placed in position. This operation is repeated until the desired number of fins have been placed upon the U-tubes and slide 228 has reached its extreme upward position, as explained in detail above.

U-tube holding mechanism The means for holding the U-tubes is best shown in Figures 5 and 6 and comprises a fixed frame I8I which is built as part of the base of the machine and a sliding rack I42 which is adapted to receive a set of three U-tubes in each of its two sections. Sliding rack I42 is carried by frame I8I, the bottom of sliding rack I42 being held by retaining strip I84 so as to slide in track I83. Extending along the back (to the right in Figure 6) of sliding rack I42 is rigidly mounted a guide strip I85 which is T-shaped in cross-section and which slides in 9. corresponding groove in frame I8I. Rack I42 is thus rigidly held and adapted to be slid horizontally along the length of track I83 by either of handles I98, and is limited in the two extremes of its movement by stop plates I191.

When rack I42 is in the position shown in Figure 5, the left-hand section thereof is positioned so that the set of U-tubes therein may receive fins; and the right-hand section is positioned so that the Utubes, with fins placed thereon, may be removed and a new set of U-tubes placed therein. When placing the U-tubes in position, the bottom of the U-tubes is received in a suitably shaped recess I88 and the top is received by holding strip I81. Holding strip I81 is best shown in Figure 4, and is provided with three cut-out portions I81a, I81b, and I81c, each of which receives a U-tube under slight tension.

A holding strip I81 is resiliently held in a horizontal position near the top of one side of rack I42 by means of a spring-pressed side bar I88. Each section of rack I42 is provided with a side bar I88, it being located in each case on the inside of the vertical wall of the rack (along the left wall of the left section and along the right wall of the right section) and supported by means of springs I89. Side bar I88 is adapted to push resiliently against one end of holding strip I81 so as to hold the other end thereof against the;

opposite side of the section. As the first fin moves downwardly upon a set of U-tubes, it will engage the top of holding strip I81, moving it downwardly. After the first fin starts moving downwardly upon the U-tubes, the tops of the U-tubes will be held in position by the fin and it will be no longer necessary to hold the tops of the U-tubes by other means. Holding strip I81 is moved downwardly to the position shown in the right-hand section of Figure 5, and may then be removed with the completed unit and may be replaced to its proper position so as to hold a new set of U-tubes.

Mounted in holes in guide strip I85 and on the center line of the left and right sections are sleeves I90 and I90, respectively, which are adapted to receive in their center holes locking pin I8I, which is slidably carried in sleeve I92 in fixed frame I8I. In Figure 5, pin I9I is inserted in sleeve I90, thereby locking rack I42 in position. When desirable, pin I9I is withdrawn from sleeve I90, rack I42 is moved to the left and pin I9I is inserted in sleeve I80. Rack I42 is thereby locked in the proper position for fins to be placed upon U-tubes in the right-hand section of the rack.

Locking pin I9I is moved to and from its locking position through a pin and slot connection by arm I93 which is rigidly mounted upon 5 .81

I94. Shaft I84 is mounted in the base of the press and extends out at both sides so that it may be operated from one side (Figure 1) by a suitable handle I89, and from the other side (Figure 3) by handle I85.

Safety stop mechanism During the operation of this machine, it is desirable that the machine automatically stop in case of obstruction. A means for accomplishing this is shown in Figures 15, 16 and 17 and is means (shown also in Figure 1) for receiving power from the main drive shaft of the press through chain 3 and transmitting the power through another chain 809 to the upper shaft 2Il of the fin-positioning means. Supported upon side frame member 2| 4 by suitable spider structure is sleeve bearing 300. Suitably supported in a like manner, concentric with sleeve bearing 300, and extending through a hole 30I in side frame member 2, is sleeve bearing 302. Extending through bearings 300 and 302 is main drive sleeve 304. Sleeve 304 is held from endwise movement 'with respect to bearing 302 by thrust bearings 308 and 308. Keyed to the left end of sleeve 304 is main drive sprocket 3| 0 which is driven by a chain 3 from the main drive shaft of the press (see Figure 1).

Rotatably mounted on sleeve 304 adjacent thrust bearing 308 is driven sprocket 3I2 which, as best shown in Figure 16, has a hub portion 3I3 into the left end of which are cut a plurality of notches. These notches are each provided with one face 3, which is in a plane parallel to and extending through the axis of rotation, and one sloping face 318. Slidably mounted upon sleeve 304 and having one face adjacent the notched end of hub 3I3 is collar 3I8. Collar 3I8 is provided with projections 3I9 which are of the same size and configuration as the notches in hub 3I3 so that the adjacent end faces of hub 3I3 and collar 3I8 normally register with each other, there being faces 3" upon collar 318 to correspond to faces 3I6 on hub 3I3. Referring to Figure 15, collar 3I8 is slidably keyed to sleeve 304 by means of key 320, so that collar 3I8 must rotate with sleeve 304 but may slide axially thereon. The center portion of collar 3I8 has an enlarged flange thereon which is provided with suitable recesses to receive one end of each of a set of four springs 322. Adjustably mounted upon sleeve 304 and adapted to receive the other ends of springs 322 is spring-retaining collar 324. Extending radially through slots 326 in sleeve 304 and rigidly mounted at its ends in collar 324 and at its center in adjusting bar 328 is pin 330. The left end of the hole in sleeve 304 is threaded and is provided with adjusting screw plug 332 and lock screw plug 334. In assembling the parts, adjusting screw plug 332 is turned into the threaded end of sleeve 304 until adjusting bar 328 is engaged and pushed to the right so as to move pin 330 along slots 328; carrying collar 324 a distance sufiicient to provide the desired tension upon springs 322. Lock screw plug 334 is then turned tightly against screw plug 332.

Extending radially through slots 338 in sleeve 304 and rigidly mounted at its ends in collar 3I8 and at its center in operating shaft 338 is pin 340. Shaft 338 is slidably mounted in sleeve 304 and has mounted upon the right end thereof bevel disc 342. Pin 340 thus limits the movement of operating shaft 338 and bevel wheel 342 to an axial movement a distance equal to the length of slots 336 and makes the position of bevel wheel 342 dependent upon the position of collar 316. Bevel wheel 342 may be moved by collar 318 from the position shown in Figure 15 to the position shown in Figure 16, but these elements are normally retained in the position shown in Figure 15 by spring 322.

Rotatably mounted in side frame members 214 and 215 adjacent bevel disc 342 is shaft 210, referred to above, upon which is rigidly mounted arm 346 which carries upon its free end, in the path of movement of the beveled edge of disc 342, a roller 348. When bevel disc 342 is moved from the position shown in Figure 15 to the position shown in Figure 16, roller 348 is engaged and shaft 210 is rotated, moving handle 350 downwardly which, as will be explained later, stops the operation of the entire machine.

In the normal operation of the machine, sprocket 316 moves clockwise (Figure 1), driving sleeve 384 which rotates collar' 316 and through it hub 313 of sprocket 312, collar 318 being normally held in engaging relationship with hub 313 by means of springs 322. Thus, it will be seen that sprocket 312 is normally driven through engaging faces 316 and 311, previously described, the pressure upon springs 322 being adjusted by means of adjusting screw plug 332 so as normally to overcome the force tending to cause faces 31'! to slide on faces 316. If, however, the operation of the machine is obstructed by abnormal load or otherwise, the force tending to cause faces 3" to slide on faces 316 will overcome the force of springs 322 and collar 318 will slide to the left against the pressureof springs 322 to the position shown in Figure 16. Sprocket 312 will, therefore, cease rotating and the fin-positioning means will stop. At the same time, this movement of collar 318 is transmitted through pin 348 to operating shaft 338 with the result that bevel disc. 342 is moved to the left. As bevel disc 342 moves to the left, it engages roller 348 and pushes upwardly thereon so as to rotate shaft 2'10 and move handle 358 down wardly so as to stop the machine.

It is thus seen that this drive means will carry a normal load, but if an abnormal load is encountered the entire machine will be stopped. An

example of such an abnormal load would be the a machine jamming, due to the fins not moving properly downwardly upon the U-tubes.

Stitciii'ng mechanism Referring to Figure 2, mounted upon the right side of the base of the press, and in the path of the strip of fin material 8 is stitcher 352 which is used, when one strip of material is exhausted. to fasten the end of the exhausted strip to a new strip. As best shown in Figures 21 and 22, the stitcher includes a movable cutter element 354, a movable stitcher element 356, and a fixed cutter element 358, in which are mounted a plurality of stitching needles 360. The fixed cutter element 358 is rigidly mounted upon base 362, and the movable elements 354 and 356 are mounted for limited vertical movement upon base frame 364. The movable elements 354'and 356 are each mounted by means of a plurality of screws which extend downwardly through base frame 364.

The left-hand side of Figure 20 is cut away so as to show one of screws 366, the lower end of which is securely threaded in movable stitcher the enlarged upper portion of 'hole 368. spring 316, within hole 368, exerts pressure upwardly on the head of screw 366 so as to tend to retain screw 366, and thus movable stitcher element 356, in the upper position 'shown in Figures 20, 21 and 22.

The upper right-hand side of Figure 20 is cut away to show one of screws 312, which are identical with screws 366 and are mounted in holes 314 with springs 316 so as normally to retain movable cutter element 354 in the upper position shown, in Figure 22.

Referring to the upper portion of Figure 20 and to Figure 18, rockably mounted in recesses 3'18 upon pivots 380 and normally positioned as shown in Figure 18 are two cam arms 382 and 384. These cam arms are connected to each other by means of bar 366; and cam arm 384 has handle extension 388 thereon which is used to operate both of the cam arms. On the lower end of each of these cam arms 382 and 384 are two cam portions which are selectively used to operate either movable cutter element 354 or movable stitcher element 356. As shown in both Figures 20 and 21, the left-hand cams 390 are positioned so that when handle 388 is swung to the left (Figure 20) cams 390 move cutter element 354 downwardly, from the position shown in Figure 22 to the position shown in Figure 21. Right-hand cams 392 are so positioned that when handle 388 is swung to the right cams 392 move stitcher element 356 downwardly, from the position shown in Figure 22 to the position shown in Figure 23. Thus, when handle 388 is moved to the left the cutter mechanism is operated, and when handle 388 is moved to the right the stitcher mechanism is operated.

As best shown in Figure 23, each of stitching needles 360 is provided with a head portion 394 which has an inclined upper face 396, the edge of which is a cutting edge. Mounted in movable stitcher element 356 directly above each stitching needle 366 is cooperating pin 398 which is surrounded by cutting sleeve 400. Cooperating pin 398 terminates at its upper end in a head which is slidably positioned in the enlarged upper portion of hole 492. Retained above pin 368 in hole 462 by means of screw plug 4114 so as to bias pin 398 in its downward position is coil spring 466. As movable stitcher element 356 moves downwardly, the inner edge of cutting sleeve 400 cooperates with the top portion of the cutting edge of head 394 and the material therebetween is pierced. Upon further movement downwardly, movable stitcher element 356 comes to the position shown in Figure 23 wherein a portion of the material is projected upwardly in the hole in cutting sleeve 4611 by head 394 so as to displace cooperating pin 398 upwardly. The lower face of movable stitcher element 356 is pressed tightly toward the upper face of fixed element 358 so as to compress the material therebetween.

In operation, shortly before the end of an exhausted strip of material reaches stitcher 352, the forward end of a new strip is placed on top of the rear edge of the exhausted strip to the extent shown in Figure 21, and handle 388 is swung to the left. This movement of handle 388 to the left cuts 011' the ends of the two strips of material, as shown in Figure 21, and accurately squares the ends. Handles 388 is then swung to the vertical position while the cut-off ends of the two strips are removed, and theoverlapping is only enough to make the stitch and is not enough to interfere with making the flanged holes in the strip. Handle 888 is now swung to the right, and movable stitcher element 856 is thereby moved downwardly to the position shown in Figure 23. This movement pushes the two strips downwardly; puncturing the two strips and displacing portions thereof, thereby making a stitch wherever there is a needle 360, as shown in Figure 23.

Mounted to the right (Figures 21, 22, and 23) of stitching needles 880 are releasing pins 408 which are similar in structure to cooperating pins 398 and are normally held in the position shown in Figures 20, 21 and 22 by springs 0. When movable stitcher element 858 moves downwardly to the position shown in Figure 23, the material is pressed against pins 408 so as to depress them to the position shown.

As handle 388 is again moved to the vertical position, pins 408 push upwardly upon the material and release it from stitching needles 860; and pins 398 push downwardly within cutting sleeve 400 so as to push the material therefrom.

The material is now free to be moved to the right by the normal operation of the machine, and as it does so there is some possibility that the stitches formed will be abnormally thick and will interfere with the movement of strip 8. To avoid this possibility and, at the same time, improve the stitches, mounted-in line with stitching needles 360 are rollers 4I2. Rollers 4I2 are rotatably mounted upon shaft 4 which is held at its ends by brackets 8 which are rigidly mounted upon base frame 864.

As suggested above, the spacing of stitching needles 360 and fin cutter I50 (Figure 2) issuch that the line formed by the right-hand side of the stitcher heads 394 is later the dividing line between two fins. Thus, the cutter I50 will cut the material along the right-hand edge of the line of the stitches so as to free the two portions of the stitch which would otherwise cause a double thickness of metal in the fins. These portions which, in Figure 23,, are the portion of the upper strip to the right of the right-hand edge of the line of stitches and the portionof the lower strip to the left of the-right-hand edge of the line of stitches may then be removed and the edges of the fins may be smoothed out to the original position so as to eliminate practically all evidence of the stitches. The stitches formed thus perform the function of holding the two strips of material together during the time that the new strip is being threaded into the machine, but the stitches are not present in the final product.

Oiler As best shown in Figures 1 and 2, mounted to the right side of stitcher 352 is oiler 4 II, the details of which are shown best in Figures 18 and 19. Rigidly mounted upon a roller 422 in pan 4I8 are annular felt strips 420 and brake disc 424. Extending around brake disc 424 and tensioned by means of an adjustable spring 425 (see also Figure 1) to produce friction with brake disc 424 is band 426. Band 426 is attached to the side of pan 8 and is thus retained in fixed position. Pan 4I8 contains suitable oil, and as the strip of fin material rides upon felt strips 420 roller 422 revolves so as to carry the oil upwardly and apply it to the under-side of the strip. The tension upon band 428 may be adjusted so as to regulate the speed of rotation of roller 422 and Material holder The mechanism for holding the strip of fin material 8 in coiled form is holder I0, and is best shown at the right of Figure 1. In actual operation, holder I0' is located further to the right of press I00 than shown, the showing of Figure 1 being for convenience only.

Holder I0 comprises cylinder I2 which is adapted to receive, and have latched thereon by means of latches I4, coiled strip 8. Cylinder I2 is provided with suitable mechanism to control the unwinding of coiled strip 8 and is mounted upon post I6. Mounted on post I6 below cylinder I2 by means of bar I8 is a bracket structure which includes three horizontal rods 20, 22 and 24, two fixed angular rods 26 and 28 and a swinging U-shapcd brake or tension member 30. Swinging U-shaped tension member 30 comprises two'side bars which fit-along the side of strip 8 and a top horizontal portion which normally lies against coiled strip 8, as shown. Strip 8 thus unwinds as it is used and is kept under constant tension.

Control mechanism The control mechanism comprises clutch means to connect the driving motor to the main power shaft and brake means which, in the present embodiment, is applied to the main power shaft whenever the motor is disconnected. All this is associated with various safety means which prevent the operator from starting the machine except when the machine is in proper condition and which stop the machine in case of trouble.

Referring to Figure 3, the fly-wheel clutch (not shown), which, when in engaging position connects motor I40 to main power shaft I34, is moved to engaging position by a movement of rod 40 upwardly and is moved to disengaging position by movement of rod 40 downwardly. Rod 40 is carried at its lower end upon the end of pivoted arm 42 and at its upper end in control box 4I. Coiled about rod 40 near its lower end is spring 44 which is compressed between fixed U-rnember 46 at its bottom and collar 48 at its top. U-member 48 is mounted upon the base of press I00 and collar 48 is adjustably mounted upon rod 40. Spring 44 thus normally biases rod 40 in its upper position so as to tend to hold the control for fly-wheel clutch in the disengaging position. Ann 42 is pivoted upon stud shaft 50 and carries one end of bar 52. The other end of bar 52 is carried by the free end of arm 54 which is rigidly mounted upon control shaft 56.

Control shaft 56 extends the width of the base of the press and has rigidly mounted thereon, in addition to arm 54, operating pedal 58, arm 60 and (Figure 1) arm 62.

' Rigidly mounted upon main power shaft I34 is brake drum 9|, around which is mounted brake 92. Brake 92 is mounted on the frame of press I00 and is normally retained in braking position by means of spring 03 and is moved from braking position by the movement of cam arm 94 downwardly. Cam arm 94 carries at its outer end the upper end of brake control rod 85, the lower end of which is carried by arm 62. When operating pedal 58 is pushed downwardly so as to rotate control shaft 56 to the running position, brake control rod is pulled downwardly so as to operate cam arm 84 and thus release brake 92 from brake drum when control shaft 58 then rotates to the stopped position, cam arm 04 will be moved upwardly and spring 03 will again be allowed to apply brake 92 to brake drum 9|.

Brake 92 is, therefore, released and motor I40 is connected to main power shaft I34 whenever operating pedal 58 is pushed to its down position; and brake 92 is immediately applied and motor I40 is disconnected whenever operating pedal 58 is moved to its up position. Due to the biasing of rod 40 by spring 44 and the biasing'of brake 92 by spring 93, the fly-wheel clutch and brake 92, and with them control shaft 56, are normally retained in the stopped position of the press.

Referring again to Figure 3, arm 00 carries at its free end one end of latch-operating rod 65, the other end of which is carried by latch 58 which acts as latching means to latch the press in either the stopped or running condition. Latch 66 is pivotally mounted upon stud bolt 68 so as to be in the position shown in Figure 3 when the press is stopped, and so as to be moved to the position shown in Figures 3b and 30 when the control of the press is moved to the running position.

As pointed out above in connection with the description of the movement of sliding rack I52 (Figures 5 and 6) when handle I95 is in the down position, shown in Figure 3, pin I9I is properly positioned in one of the .two sleeves I90 or I90, showing that sliding rack I42 and thus a set of U-tubes are properly positioned. If handle I95 is moved to its upper positiomshown in dotted lines in Figure 3, pin I9I will be withdrawn and sliding rack I42 will be free to move. It is desirable that the machine not be started except when sliding rack I42 is locked in a proper position by pin I9I.

To perform this function, extending downwardly from handle I95 is operating rod I8 which is connected at its lower end through pivot pin I6 to the left end of latch bar I0 which is pivoted on stud 72 and in the right end of which is formed a notch I4. With latch 66 in the stopped position, shown in Figure 3, when handle I95 is raised so as to withdraw pin I 9| notch I4 falls over the end of latch 66 so as to prevent clockwise rotation of latch 66. It will thus be seen that when pin iQI is withdrawn, latch 66, latch operating rod 04 and arm 60 will be held fixed, thereby preventing movement of control shaft 56 and the machine cannot be started.

During the time that the machine is running, it would be undesirable to withdraw pin I9I because of the possibility of accidental movement of sliding rack IE2. With the machine in the running position, latch 65 will be in the position shown in Figure 3c; and any attempt to pull up on handle I85 will cause the right end of latch bar I0 to engage the top of latch 66, as shown in Figure 3c, and so prevent handle I95 from being moved enough to withdraw pin ISI. Operating rod I8, latch bar I0, latch 66 and latch operating rod 64, therefore, cooperate so as to prevent the starting of the machine after pin I9I is withdrawn and so as to prevent the withdrawal of pin I9I while the machine is running.

Freely mounted upon stud bolt I2, between latch bar I0 and the side wall, is latch arm 80 which, as best shown in Figures 3a and 3b, is connected through a pin and slot connection at its free end with operating arm 82. Operating arm 82 is rigidly mounted upon shaft 84 which has rigidly mounted thereon arm 86. Arm 80 is connected through rod 88 to operating handle 350 which, as pointed out above, is rigidly mounted upon shaft 210. Attached at one end to handle 350, and at the other end to side frame member 2| 5, is spring 90 which normally biases handle 350 upwardly. It will be seen that when latch 56 is moved clockwise from the position shown in Figures 3 and 3a to the running position, shown in Figure 3b, spring 90 will pull upwardly upon handle 350, thereby carrying rod 88 and arm 86 upwardly and rotating shaft 84 and arm 82 counterclockwise so that latch arm 80 will fall and notch 8| will catch on the left side of latch 86, as shown in Figure 3b. Latch 66, and with it latch operating rod 64, arm 60 and operating shaft 56, will thus be retained in the running position by latch arm 80.

As pointed out above in connection with the description of the normal stopping of the machine when a unit is completed and the stopping of the machine by the safety stop mechanism, if shaft 210 is rotated soas to push downwardly on handle 350 latch arm 80 will be raised and, due to the action of springs 64 and 03, control shaft 56 will be moved to the stopped position.

In accordance with the provisions of the patent statutes, I have described the principles of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof, but I desire to have it understood that the apparatus shown and described is only illustrative and that the invention may be carried out by other means.

I claim:

1. In apparatus for the production of metal parts from strips of sheet metal, attaching means for interlocking the end of one strip of metal to the strip which is to follow it, a die to deform the metal, metal cutting means to cut the metal part from the strip and means to feed the sheet metal through the apparatus, said attaching means and said cutting means being spaced in such a position that the interlocking produced by the attaching means will be on a line where cutting will occur. I

2. In apparatus for the production of metal parts from strips of sheet metal, attaching means for interlocking the end of one strip of metal to the strip which is to follow it, a die to deform the metal, metal cutting means to cut the metal part from the strip, and means to feed the sheet metal through the apparatus, the attaching means and the cutting means being spaced in such a position that the interlocking produced by the attaching means will be on a line where cutting will occur, and the interlocking means between the sheets of metal being of a type that when out the ends of the two strips of metal, which represent the overlapping of metal to form the interlock, may be removed.

3. In a machine of the character described, the combination of, means for producing elements having holes therein, means to place them upon longitudinal members, and control means which allows the machine to be started only when the longitudinal members have been properly placed in position and which stops the machine when the desired number of elements have been placed upon the longitudinal members.

4. In a machine for attaching the adjacent edges of two pieces of sheet metal together, a

cutter comprising a fixed block having a cutting edge thereon and a first movable element having a cutting edge adapted to cooperate with the cutting edge on said fixed block, an attaching means having a second movable element mounted with said first movable element, cam means rotatably mounted and normally resting in a predetermined position so as to operate said cutter when moved to one position from said predetermined position and operate said attaching means when moved to another position from said predetermined position.

5. In apparatus of the character described, means to hold a piece of sheet metal, means to form holes in the sheet metal, means to hold pipes, and cutting and positioning means to cut portions of the sheet metal tree from the piece to form individual fins and start the movement of each fin toward and along the pipes during the cutting movement and then continue the movement of the fins along the pipes to the proper position.

6. In a finning machine of the type wherein heat exchange fins are placed upon pipes, the combination of: means to form fins; and means to receive the fins as they are formed and place them upon the pipes comprising, means to rigidly hold the pipes, means to individually receive the fins, and motive means to cause rel-" ative movement between the fins and the pipes to properly position the fins upon the pipes; and safety control means to prevent "the operation of said motive means when said means for holding the pipes is not properly positioned.

'7. In a finning machine of the type wherein heat exchange fins are placed upon pipes, the combination of means to form fins; and means to receive the fins as they are formed and place them upon the pipes comprising, means to rigidly hold the pipes, means to individually receive the fins, and motive means to cause relative movement between the fins and the pipes to properly position the fins upon the pipes; latching means operative to retain in proper position said means for holding the pipes; and interlocking means to prevent the operation of said motive means when said latching means is unlatchedwhereby the apparatus cannot be operated when said means for holding the pipes is not latched in proper position.

8. In a finning machine of the type wherein heat exchange fins are placed upon pipes, the combination of: means to form fins; fin positioning means to place the fins upon the pipes; motive means including an overload clutch to impart movement to said fin positioning means;

and control means responsive to an overload on said overload clutch-whereby the machine is stopped when an abnormal load is placed upon said fin positioning means.

9. In a finning machine of the type wherein heat exchange fins are formed and placed upon pipes, the combination of: means for producing fins; means to receive the fins as they are formed and to place them upon pipes; and control means operative to prevent the operation of the machine when the pipes have not been properly placed in position, and operative to stop the machine when the desired number of fins have been placed upon the pipes.

10. In a machine of the character described, the combination of means for producing elements having holes therein; positioning means for placing the elements upon longitudinal members; and control means including, a first linkage mechanism which is operative when moved positioned, a cooperating linkage mechanism which is normally operative to latch said first linkage mechanism in its running position, and

. combination of: means to move to a position along the ends of the pipes a portion of th sheet metal supply having holes therein, said portion corresponding to a fin; and fin severing and positioning means to sever the center portion of the fin from the sheet metal supply and simultaneously start movement of the fin onto the pipes, and then sever the ends of the fin from the sheet metal supply and proceed with the positioning of the fin.

12. In a finning machine which makes fins from sheet metal and places the fins upon pipes, the combination 0!, hole-forming means to form holes in the sheet metal, fin severing and moving means to cut the individual fins from the sheet metal and simultaneously start movement of the fins onto the pipes in one operation.

13. In a finning machine which makes fins from sheet metal and places the fins upon pipes, the combination oi: metal deforming means to shape the sheet metal; and fin severing and mov-. ing means to cut the individua fins from the sheet metal and simultaneously start movement of the fins onto the pipes; said fin severing and moving means comprising, two cutters mounted to have relative movement and having complementary cutting edges, each ofsaid cutters having a main cutting edge in one plane and two auxiliary cutting edges in another plane, the two planes 01. each cutter being parallel and spaced a predetermined distance apart, each of said main cutting edges having a straight-line center portion and arcuate end portions, the auxiliary cutting edges of each cutter having the samecurvature as the arcuate end portions of the main cutting edge on the other cutter and being adapted to cooperate therewith-whereby, when said cutters are moved together, the central portions of the two main cutting edges first cooperate to sever the central portion of the fin from the sheet of metal and the fin is thenfirst sleeve having a cutting edge about one end of its center hole, a second tool-carrying member rigidly carrying a cutting pin mounted to coact with said cutting edge to out a hole in sheet metal therebetween, a second sleeve surrounding said cutting pin and yieldably carried by said second tool-carrying member, a third sleeve surrounding said second sleeve and rigidly mounted upon said second tool-carrying member to move onto the end of said fixed sleeve .and coact with said fixed sleeve to form the sheet metal around the hole into a sleeve.

15. In apparatus for producing sheet metal straight-forward 2,224,549 parts, the combination of, hole-forming means to produce holes in a strip of sheet metal, severing means to cut the sheet metal into the individual parts, and positioning means located along the path of movement of the sheet metal between said hole-forming means and said severing means to advance the sheet metal through the machine, said positioning means including an oscillating finger unit having means to enter and engage the sides of the holes which are formed in the meta1 and to move the sheet metal by this engagement-whereby the sheet metal is positioned with respect to said severing means depending upon the relative position of the holes formed in the sheet metal.

16. In apparatus for the production of metal parts from strips of sheet metal, attaching means for interlocking the end of one strip of metal to the strip which is to follow it, a die to deform the metahmetal cutting means to cut the metal part from the strip, and means to feed the sheet metal through the apparatus, said attaching means and said cutting means being spaced in such a position that the interlocking produced by the attaching means will be on a line where cutting will occur, and said attaching means comprising a plurality of units each of which comprises a needle having a portion to pierce and interlock the overlapping ends of the strips and means to cooperate with said needle to insure that said interlocking occurs.

1'7. In a finning machine which makes fins from sheet metal and places the fins upon pipes, the combination of metal deforming means to shape the sheet metal; and fin severing and moving means to cut the individual fins from the sheet metal and simultaneously start movement 01' the fins onto the pipes; said fin severing and moving means including, a cutter having a main cutting edge in a first plane and two auxiliary cutting edges in a second plane, said second plane being parallel to said first plane and spaced -a predetermined distance therefrom, said main cutting edge having a straight line center portion and arcuate end portions, one of said auxiliary cutting edges extending from a point adjacent the point of juncture of said center portion and each of said arcuate end portions, said cutter having a raceway for discarded material extending away from said main cutting edge and starting in the plane of said auxiliary cutting edges.

18. In a finning machine which makes fins" from sheet metal and places the fins upon pipes, the combination of: metal deforming means to shape the sheet metal; and fin severing and moving means to cut the individual fins from the sheet metal and simultaneously start movement 5 of the fins onto the pipes; said fin severing and moving means comprising, two cutters having complementary cutting edges, one cutter being movable with respect .to the other, each cutter having a main cutting edge in a first plane and 10 two auxiliary cutting edges in a second plane, the first and second planes of each cutter being parallel and spaced a predetermined distance apart, each of said main cutting edges having a straight line center portion and arcuate end- 5 portions, one of said auxiliary cutting edges of each cutter extending from a point adjacent the point of juncture of the center portion and each of the arcuate end portions of the main cutting edge, the auxiliary cutting edges of each 20 cutter being of the same contour as the arcuate end portions of the main-cutting edge of the, other cutter and being adapted to cooperate therewith, one of said cutters having a pair of raceways for discarding material one of which 25 raceways extends from each set of auxiliary cutting edges to thereby provide an outlet for material severed from the corners of the fins by the auxiliary cutting edges.

19. In a finning machine which makes fins 30 from sheet metal and places the fins upon pipes, the combination of: metal deforming means to shape the sheet metal; and fin severing and moving mean-s to cut the individual fins from the sheet metal and simultaneously start move- 35 ment of the fins onto the pipes; said fin severing and moving means comprising, two cutters mounted to have predetermined relative movement, each of said cutters having cutting edges in a first plane and in a second plane, said first 40 and second planes of each cutter being spaced apart a predetermined distance, each of said cutters having a first cutting edge in its first plane and second and third cutting edges in its second plane, said second'cutting edge of one 45 cutter being adapted to cooperate with the second cutting edge of the other cutter and the first cutting edge of each cutter being adapted to cooperate with the third cutting edge of the other cutter. 50

- WILLIAM L'. O'BRIEN. 

